A Facile Synthesis of quinoxalines and dicyano pyrazines using Ca(IO3)2 as efficient and recycling catalyst

Quinoxaline derivatives are an important class of nitrogen containing heterocycles and have been widely used in dyes pharmaceuticals and electrical/photochemical materials. Also, quinoxaline ring moiety is a part of various antibiotics such as Echinomycin, Levomycin, and Actinoleutin that are known to inhibit growth of gram positive bacteria, and are active against various transplantable tumors [1]. Also, dicyanopyrazine derivatives have been synthesized and are valuable in a broad range of chemistry fields due to their applications as functional dyes, nonlinear optical materials, etc. [2]. Because of their importance, up to now, several methods have been reported for the synthesis of these compounds including the condensational reaction of an aryl 1,2-diamine with a 1,2-dicarbonyl compound in refluxing or in the presence of an acid catalyst under various reaction conditions [3].Looking at the above facts, in this study, we report use of Ca(IO3)2 as an efficient heterogeneous catalyst for the preparation of 2,3-diaryl quinoxaline and dicyano pyrazine derivatives by reaction of o-arylenediamine or diaminomaleonitrile and 1,2-dicarbonyl compounds. The attractive features of this procedure are its good conversions, easy workup, and short reaction times, safely and recyclable catalyst, making it a useful practical method for the synthesis of the title compounds